


The Dark One

by merlin_the_dragonlord



Series: 13 Days of Darkness [1]
Category: Merlin (TV)
Genre: Alternate Universe - Once Upon a Time Fusion, Dark Merlin, Implied/Referenced Character Death, M/M
Language: English
Status: Completed
Published: 2016-10-19
Updated: 2016-10-19
Packaged: 2018-08-23 09:04:38
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,474
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8322052
Author URL: https://archiveofourown.org/users/merlin_the_dragonlord/pseuds/merlin_the_dragonlord
Summary: Get the Dark One's dagger. That's the only way to stop him. 
There's a new Dark One in town and Arthur's determined to stop him.





	

**Author's Note:**

> This is the first installment of the challenge I'm doing, where for the 13 days leading up to Halloween, I'll post a story that involves either dark!Merlin or dark!Arthur. 
> 
> This is a fusion with Once Upon a Time, where the Dark One is the embodiment of dark magic and supposedly the most powerful being in existence.

_Get the Dark One’s dagger. That’s the only way to protect your loved ones._ That was the mantra running through Arthur’s mind as he looked around the bedroom. Merlin was downstairs, preparing tea for his guest. He didn’t have much time.

There were a limited number of places where Merlin could have hidden the dagger. Arthur _knew_ it was in here somewhere. It had to be. He had searched every other possible place where Merlin could have kept such a precious item. Maybe… Maybe it was under the floorboards. That was where he had kept his magic book and staff while in Camelot after all. He got down on his hands and knees and looked under the bed. It was dark and Arthur couldn’t see much. Twisting a little, he grabbed his cell phone from where he had tossed it on the bed and turned the flashlight on. There didn’t seem to be any loose floorboards of any sort from what he could see, but to be safe, he ran a hand across the wood. To his surprise, one of the boards shifted. He moved it and reached in carefully. There was a cool, smooth something and he wrapped his hand around it. He held his breath in a silent prayer as he pulled it out. _Merlin Emrys_. The jagged dagger gleamed as the sunlight through the window hit it. “Found it, you bastard.”

“Congratulations.” He jumped at the sudden noise and whirled around, brandishing the dagger. “Careful now, wouldn’t want you to injure yourself.” Merlin was leaning against the wall, arms crossed. There was an amused glint in Merlin’s eyes as he surveyed Arthur.

“I found your dagger. You have to do as I say now.”

“Is that how this works?” Merlin raised an eyebrow. With a grace that Arthur didn’t even realize he had possessed, he pushed himself off the wall and approached him.

Arthur panicked. “Stay back!”

Merlin stopped in place. His eyes were wide as he looked down.

“It does work.” He sighed in relief. There was a brief moment of fear where he thought that maybe the dagger was fake. “Thank God.”

“Maybe God isn’t the one you should be thanking.” Arthur stiffened when he felt air on his neck. How… “I’m almost insulted. Did you really think I was still that stupid?” Merlin shoved Arthur lightly. “No, that dagger’s a fake.” He waved a hand and Arthur’s hands were empty. “The real dagger is _very_ well hidden.” Arthur turned. “But I’m disappointed in you, Arthur. I thought you were better than this.” There was so much _hurt_ in Merlin’s voice. Arthur had to remind himself that none of it was real. “I see your friends have been a bad influence on you.” That made Arthur’s blood run cold.

“You leave them alone.” He snarled out. He didn’t even care if he no longer had a weapon. He would wring Merlin’s skinny neck with his bare hands if it meant that his friends were safe.

“Oh don’t worry. As long as they don’t disturb us, I won’t do anything to him.” Merlin said lightly. “But this does mean you get to stay with me for a while.” He waved his hand and his eyes glowed gold.

“Wait a min-“ _Thud_. Arthur hit the ground, out cold.

“Sorry, love.” 

* * *

  _It hurt. There was so much pain._ Arthur clenched down hard, trying not to scream. His entire body was white-hot with pain. There was light pressure on his chin and his face was tilted upwards. He saw the blurry outline of a person in front of him. He knew it was Merlin.

“Aren’t you a sight for sore eyes?” The voice was gentle and Arthur had to bury the hope that rose up within him. He knew that it was all a lie. “Oh, love.” There was a warmth that ran through him and he felt the pain subside.

“Why are you here?” Arthur demanded, glaring up at the now clear figure.

Merlin arched an eyebrow and stepped back. “I wanted to see my lover, is that such a crime?” He pouted mockingly. Arthur remembered the days when he would kiss that pout away. He hated it now.

“You’re not my lover.” Arthur spat out. All he saw was Merlin’s eyes narrowing before there was another surge of pain. It took him by surprise and he screamed.

As quickly as it came, it disappeared and there was soft cooing. “I’m sorry, love. I’m so sorry. I just… hate it when you talk like that.” Merlin was now kneeling in front of him and his hands came up to cradle Arthur’s face. “I love you.”

“Then give me your dagger.” Merlin frowned at the demand. “If you love me, give me your dagger.”

“You know I can’t do that.” Merlin said softly. “You promised me that you would never…”

“You killed Morgana!” Arthur growled out. “You killed her and…” _You hurt Gwen_.

“She was plotting against you.” Merlin’s voice was filled with so much conviction that it pained Arthur to know that Merlin was so convinced he had done the right thing. “She was going to kill you.”

“Merlin, please. Just… Just give me your dagger and I’ll forgive you. I’ll know that you love me.” Arthur couldn’t force himself to say the words that had come so easily to him before. _I’ll love you again._ He had never stopped loving Merlin, but the being in front of him wasn’t his Merlin.

“There’s nothing to forgive.” His tone left no room for argument. “I’ve done nothing wrong.” He rose fluidly. “You… You’ll stay here. You’re safe here, Arthur.” He turned away. “I thought… Never mind.” The door shut, leaving Arthur in darkness again.

He had to swallow down his scream. It hurt, it all hurt so much. This wasn’t his Merlin.

Minutes passed, maybe hours, maybe days. He didn’t know. Merlin had cast some sort of spell over him so he wouldn’t need food or sleep. Merlin’s magic was sustaining him now. The door opened again and Arthur had to shut his eyes to shield from the sudden influx of light.

“Arthur?” That voice was familiar, but he couldn’t quite place it. “Arthur, oh god…” He wondered what he looked like now. “Arthur, look at me.” A shadow fell across his face.

“G-Gwen…” He started shaking. “Y-You need to leave… He’ll kill you…”

“I’m hurt that you would think that badly of me.” Arthur finally opened his eyes to see Merlin standing behind Gwen, eyes glowing gold. An invisible force yanked her away and pinned her against the opposite side of the cell. She shrieked as her body hit the wall. Merlin had not been gentle.

“Gwen, run!” Arthur lunged forward, ignoring the searing pain in his wrists as the handcuffs tugged at his skin. He _had_ to save Gwen. He would not let Merlin harm anyone else on his behalf. He saw golden eyes narrow and the only warning he got before his world went black again was Merlin waving his hand.

“Arthur!” Gwen screamed his name and her struggle intensified.

Merlin strode over to her, a scowl on his face. “You couldn’t leave him alone, could you?” He spat out. “Look at what you made me do.”

“This isn’t you, Merlin. This can’t be you. You’re our friend!”

He stared at her and for a moment, Gwen felt some hope that maybe she was getting through to the Merlin that she knew and loved. All of that hope disappeared when he started laughing. “Oh, Guinevere.” He reached out a finger to brush back her curls. She flinched away from the touch. “You’re so naïve. Kind-hearted, yes, but so naïve.” He cocked his head. “You know, I think Arthur could do with a friend while he comes to his senses. That could take a while. You know our Arthur, so stubborn.” A smile spread across his face. “Yes, I think…” He placed a hand on her cheek. “Don’t move too much, dear Guinevere. This spell is particularly complex and the consequences of me messing up would not be pleasant for you.”

Her eyes widened. “Merlin, please don’t do this.” She pleaded. “You’re still in there somewhere, I know it!”

“Unfortunately, the Merlin you knew from Camelot is long dead, _Your Majesty_.” She closed her eyes at the title that she hadn’t heard in almost a millennium. “Only Emrys remained. And now… Well, the Dark One is back.” He laughed again. “Now… where was I? Oh yes. Stay still.” She wanted to be contrary, wanted to struggle and fight back, but she found herself frozen as magic flowed through her. Surprisingly, his magic was warm. It almost felt nice, but as he continued the spell, everything became hotter…. And hotter…. It felt like liquid fire was coursing through her veins. She screamed.

**Author's Note:**

> Reviews give me life and motivate me to actually finish this challenge.


End file.
